Field of the Invention
The invention generally relates to methods for adjusting an adaptive screen-refresh rate, and more particularly, to methods for adjusting an adaptive screen-refresh rate and devices thereof for balancing system power consumption and user experience in the case of insufficient screen-refresh rate provided by a display source.
Description of the Related Art
Recently, electronic devices with display functions have become more and more popular. Generally, users can use displaying modules (e.g., screens) of electronic devices to view texts, videos, etc. For example, users can use displaying modules of the electronic devices to read e-books, browse the web, watch videos, paly games and so on. The electronic device may be a device of a computing device, a portable or mobile device, a wearable device, or the like. For example, the electronic device may be one of the devices or a portion of a device of a smart phone, a smart watch, a smart bracelet, a smart necklace, a personal digital assistant or a computing device (e.g., a tablet, a laptop, a notebook, a desktop computer, a server, etc.) or part of a device. With the advancement of technology, in order to pursue the better experience of visual effect, users have been increasingly demanding on the smoothness of the videos or the game images. However, because the above-mentioned electronic devices (especially, portable electronic devices) are often equipped with batteries for power supply, it is necessary for the users to pay attention to the power consumption of the electronic devices while providing smooth images to the users.
Taking a mobile phone using Android operating system (Android) as an example, the system needs to ensure that the display device refreshes the display screen with an appropriate screen-refresh rate. A screen with a higher screen-fresh rate often consumes more power, and a screen with a lower screen-fresh rate often makes the users feel that the video they are watching is discontinuous, thereby affecting the user experience. In current Android operating system, the preset screen-fresh rate is set at 60 frames per second (FPS). That is, the screen-fresh rate set by the system for the screen is 60 Hz (which can also be expressed as 60 FPS). This is mainly due to two reasons. First, the human eye cannot feel the screen refreshing itself at 60 FPS, allowing users to enjoy the watching experience. Second, the display screen of mobile phone today is commonly developed based on the 60 FPS screen-fresh rate as the standard. The Android system may send a Vertical-Sync (V-Sync) signal at a frequency of 60 Hz (every 16.6 milliseconds) based on the principle of displaying 60 FPS.
However, in a specific mobile phone application, sometimes the screen-fresh rates provided or required by display sources are less than 60 FPS. For example, when a video is played, highly-loaded game is allowed, or the screen is not in use, the screen-fresh rate setting of the display source of the display screen can be lower than 60 Hz. Although the screen-fresh rate provided by the display source is less than 60 FPS, the system defaults to configure the displaying module still to refresh the screen at the screen-refresh rate of 60 FPS, so the system will consume additional power. Moreover, because the screen is repeatedly refreshed at a fixed screen-fresh rate, when a different display source is generated and it is not at the time of refreshing the screen, it will wait for a certain period of time to be refreshed and displayed, which may cause a display delay and greatly reduce the user experience. It is therefore a desire to have a method and a device for adjusting screen-refresh rate to balance system power consumption and user experience when the screen-refresh rate provided by the display source is less than the preset one.